By Tina Hesman Saey DENVER — The action of tiny hair-like appendages on cells can mean the difference between fat and thin. Now scientists have a better idea of how the little hairs, called primary cilia, control appetite. Primary cilia — single, hairlike projections that all cells in vertebrates usually have — seem to sequester a protein that senses and responds to an appetite-stimulating hormone, Nicolas Berbari of the University of Alabama at Birmingham reported December 6 at the annual meeting of the American Society for Cell Biology. In people and mice that lack primary cilia, the appetite stimulant works overtime, leading to overeating and obesity, Berbari said. These findings may lead to new ways to control appetite and prevent or reverse obesity. And the study may help scientists better understand the process of eating, said Kirk Mykytyn, a cell biologist at Ohio State University in Columbus. “This work is important because it’s more thoroughly clarifying the molecular mechanism involved in obesity associated with the loss of cilia,” he said. access People with Bardet-Biedl syndrome have defects in genes responsible for building primary cilia. A prominent consequence of the disease is obesity. Working with mice that also lack primary cilia due to defects in the same genes, Berbari and his colleagues tried to figure out exactly how the cellular appendages are involved in appetite. © Society for Science & the Public 2000 - 2011

Keyword: Obesity
Link ID: 16132 - Posted: 12.10.2011

by Robert Kowalski What is the relationship between language and thought? The quest to create artificial intelligence may have come up with some unexpected answers THE idea of machines that think and act as intelligently as humans can generate strong emotions. This may explain why one of the most important accomplishments in the field of artificial intelligence has gone largely unnoticed: that some of the advances in AI can be used by ordinary people to improve their own natural intelligence and communication skills. Chief among these advances is a form of logic called computational logic. This builds and improves on traditional logic, and can be used both for the original purpose of logic - to improve the way we think - and, crucially, to improve the way we communicate in natural languages, such as English. Arguably, it is the missing link that connects language and thought. According to one school of philosophy, our thoughts have a language-like structure that is independent of natural language: this is what students of language call the language of thought (LOT) hypothesis. According to the LOT hypothesis, it is because human thoughts already have a linguistic structure that the emergence of common, natural languages was possible in the first place. The LOT hypothesis contrasts with the mildly contrary view that human thinking is actually conducted in natural language, and thus we could not think intelligently without it. It also contradicts the ultra-contrary view that human thinking does not have a language-like structure at all, implying that our ability to communicate in natural language is nothing short of a miracle. © Copyright Reed Business Information Ltd.

Keyword: Language; Attention
Link ID: 16131 - Posted: 12.10.2011

By Shaun Nichols It seems obvious to me that I have free will. When I have just made a decision, say, to go to a concert, I feel that I could have chosen to do something else. Yet many philosophers say this instinct is wrong. According to their view, free will is a figment of our imagination. No one has it or ever will. Rather our choices are either determined—necessary outcomes of the events that have happened in the past—or they are ­random. Our intuitions about free will, however, challenge this nihilistic view. We could, of course, simply dismiss our intuitions as wrong. But psychology suggests that doing so would be premature: our hunches often track the truth pretty well [see “The Powers and Perils of Intuition,” by David G. Myers; Scientific American Mind, June/July 2007]. For example, if you do not know the answer to a question on a test, your first guess is more likely to be right. In both philosophy and science, we may feel there is something fishy about an argument or an experiment before we can identify exactly what the problem is. The debate over free will is one example in which our intuitions conflict with scientific and philosophical arguments. Something similar holds for intuitions about consciousness, morality, and a host of other existential concerns. Typically philosophers deal with these issues through careful thought and discourse with other theorists. In the past decade, however, a small group of philosophers have adopted more data-driven methods to illuminate some of these confounding questions. These so-called experimental philosophers administer surveys, measure reaction times and image brains to understand the sources of our instincts. If we can figure out why we feel we have free will, for example, or why we think that consciousness consists of something more than patterns of neural activity in our brain, we might know whether to give credence to those feelings. That is, if we can show that our intuitions about free will emerge from an untrustworthy process, we may decide not to trust those beliefs. © 2011 Scientific American,

Keyword: Attention
Link ID: 16130 - Posted: 12.10.2011

Virginia Gewin Rats, often anthropomorphized as greedy and selfish, may not be the callous, cartoon villains they are sometimes made out to be. A paper published today in Science demonstrates that the rodents will liberate trapped cage-mates — even when they have nothing to gain1. There is a growing body of research showing that animals respond to the emotions of others. But it wasn't certain whether rats could suppress their own distress in order to aid another rat. Lead author Peggy Mason, a neurobiologist at the University of Chicago, Illinois, thinks her work is a significant step towards settling this question. “This finding is the big kahuna — evidence that empathy motivates one individual to help another,” she says. Following a two-week introduction period, pairs of rats were put inside an arena. One was trapped inside a central restrainer, while the other roamed free in the larger space. By day six or seven, on average, the roaming rat learned to free the trapped rat. The free rats seldom opened empty containers or those containing a toy rat. Although fewer in number, all the female rats tested became door openers; whereas 30% of males never became door openers. © 2011 Nature Publishing Group,

Keyword: Emotions; Aggression
Link ID: 16129 - Posted: 12.10.2011

By PAMELA PAUL IF you believe men think about sex all day long, you’re wrong. According to a study to be published in the January issue of The Journal of Sex Research, the statistic oft-cited by the sex-obsessed or those critical of the sex-obsessed — that men think about sex every seven seconds — is way off. “The story about this paper that’s been reported in the press has been ‘Men think about sex 19 times a day!’ ” said Terri Fisher, a psychology professor at Ohio State University at Mansfield, and the study’s lead author. But that isn’t all that much when you consider the study’s participants were college students, those repositories of raging hormones and unfettered urges. “The more interesting finding is that male college students think just as much about food and sleep as they do about sex,” Dr. Fisher said. To determine how much time people devoted to such thoughts, the researchers asked 283 students age 18 to 25 to use clickers (golf score counters), whenever they contemplated one of life’s three basic needs. Previous studies on the subject were overwhelming retroactively self-reported; researchers asked people after the fact to recollect how often they thought about sex, a method fraught with error. Of course, all kinds of caveats still apply. Did they worry about clicking too often, or too infrequently, and self-adjust accordingly? What kind of thoughts were they having? Was it, “I’d really like to sleep with my boss’s new assistant” or “I wonder whether squirrels mate in the spring?” © 2011 The New York Times Company

Keyword: Sexual Behavior; Attention
Link ID: 16128 - Posted: 12.10.2011

By Jonah Lehrer Email Author The human mind sees minds everywhere. Show us a collection of bouncing balls and we hallucinate agency; a glance at a stuffed animal and we endow it with a mood; I’m convinced Siri doesn’t like me. The point is that we are constantly translating our visual perceptions into a theory of mind, as we attempt to imagine the internal states of teddy bears, microchips and perfect strangers. Most of the time, this approach works well enough. If I notice someone squinting their eyes and clenching their jaw, I automatically conclude that he must be angry; if she flexes the zygomatic major – that’s what happens during a smile – then I assume she’s happy. The point is that a few cues of body language are instantly translated into a rich mental image. We can’t help but think about what other people are thinking about. But this intricate connection between mind theorizing and sensory perception can also prove problematic. For instance, when people glance at strangers who look “different” – perhaps they dress funny, or belong to a different ethic group – they endow these strangers with less agency, a fancy term for the ability to plan, act and exert self-control. Or consider a 2010 fMRI experiment that found that when men glance at “sexualized” women they exhibit reduced activation in parts of the brain typically associated with the attribution of mental states. These are obviously terrible habits – a hint of cleavage shouldn’t make us care less about someone’s feelings, nor should a different skin tone – but we mostly can’t help it. We judge books by the cover and minds by their appearance. We are a superficial species. © 2010 Condé Nast Digital.

Keyword: Sexual Behavior
Link ID: 16127 - Posted: 12.10.2011

by Robert Krulwich Here's something you should know about yourself. Vowels control your brain. "I"s make you see things differently than "O"s. Here's how. Say these words out loud: Bean Mint Slim These "I" and "E" vowels are formed by putting your tongue forward in the mouth. That's why they're called "front" vowels. Now, say: Large Pod Or Ought With these words, your tongue depresses and folds back a bit. So "O", "A" and "U" are called "back" of the throat vowels. OK, here's the weird part. When comparing words across language groups, says Stanford linguistics professor Dan Jurafsky, a curious pattern shows up: Words with front vowels ("I" and "E") tend to represent small, thin, light things. Back vowels ("O" "U" and some "A"s ) show up in fat, heavy things. It's not always true, but it's a tendency that you can see in any of the stressed vowels in words like little, teeny or itsy-bitsy (all front vowels) versus humongous or gargantuan (back vowels). Or the i vowel in Spanish chico (front vowel meaning small) versus gordo (back vowel meaning fat). Or French petit (front vowel) versus grand (back vowel). Copyright 2011 NPR

Keyword: Language
Link ID: 16126 - Posted: 12.10.2011

by Traci Watson Parrots have neither lips nor teeth, but that doesn't stop them from producing dead-on imitations of human speech. Now researchers have learned part of the reason: like humans, parrots use their tongues to form sounds. As they report today in The Journal of Experimental Biology, scientists took x-ray movies of monk parakeets, Myiopsitta monachus, South American natives that can be trained to speak but aren't star talkers. The parakeets lowered their tongues during loud, squeaky "contact calls" made when the birds can't see each other and during longer, trilling "greeting calls" made to show a social connection. As seen in the video, the parakeets also moved their tongues up and down while chattering. No other type of bird is known to move its tongue to vocalize. Parrots use their mobile, muscular tongues to explore their environment and manipulate food. Those capable organs, just by coincidence, also help parrots utter greetings in words that even humans can understand. © 2010 American Association for the Advancement of Science.

Keyword: Language; Evolution
Link ID: 16125 - Posted: 12.08.2011

by Greg Miller Connectivity is a hot topic in neuroscience these days. Instead of trying to figure out what individual brain regions do, researchers are focusing more on how regions work together as a network to enable memory, language, and decision-making. Now, a study of more than 100 children finds that interconnected brain regions develop in concert through childhood and adolescence. The researchers say their work could have implications for understanding various puzzles in neuroscience, such as what goes wrong in autism or why adolescent boys are prone to risky behavior. To look for evidence of coordinated development across brain regions, Armin Raznahan, a child psychiatrist and neuroscientist at the National Institute of Mental Health in Bethesda, Maryland, and his colleagues tapped into a long-running NIMH project that has been collecting magnetic resonance imaging scans of brain anatomy in children at different ages. They analyzed scans from 108 healthy children who'd had at least three scans taken between the ages of 9 and 22. The researchers calculated the thickness of the cerebral cortex, the brain's outermost layer of tissue, which is involved in virtually every aspect of cognition and behavior. In general, the cortex thickens in early childhood and thins in adolescence or adulthood, Raznahan says. He and his colleagues hypothesized that these changes might happen simultaneously in interconnected brain regions. That's exactly what they found. For example, the team will report tomorrow in Neuron, they saw this pattern in the so-called default mode network, which becomes active when people let their minds wander. "These regions are firing together for a lot of one's life," Raznahan says. "What we've shown is that these regions also seem to mature in close synchrony with each other." © 2010 American Association for the Advancement of Science

Keyword: Development of the Brain; Brain imaging
Link ID: 16123 - Posted: 12.08.2011

by Andy Coghlan The brains of children from violent homes function like those of soldiers when it comes to detecting threats. Eamon McCrory at University College London used fMRI to scan the brains of 20 outwardly healthy children who had been maltreated and 23 "controls" from safe environments. During the scans, the children, aged 12 on average, viewed a mixture of sad, neutral and angry faces. When they saw angry faces, the maltreated children showed extra activity in the amygdala and the anterior insula, known to be involved in threat detection and anticipation of pain. Combat soldiers show similar heightened activity (Current Biology, DOI: 10.1016/j.cub.2011.10.015). "Our belief is that these changes could reflect neural adaption," says McCrory. "Maltreated kids and active soldiers are adapting to survive in a threatening or dangerous environment." Although this could help children survive their early years, it may predispose them to mental health problems in adulthood, such as depression or anxiety, says McCrory. A related study, published this week by Hilary Blumberg of Yale University School of Medicine and colleagues, demonstrates that areas of the brain important for emotional processing are deficient in grey matter in adolescents who suffered from maltreatment as children (Archives of Pediatrics and Adolescent Medicine, DOI: 10.1001/archpediatrics.2011.565). © Copyright Reed Business Information Ltd.

Keyword: Stress; Development of the Brain
Link ID: 16122 - Posted: 12.08.2011

Prenatal steroids — given to pregnant women at risk for giving birth prematurely — appear to improve survival and limit brain injury among infants born as early as the 23rd week of pregnancy, according to a study by a National Institutes of Health research network. Current guidelines recommend giving prenatal steroids to women at risk of delivering between the 24th and 34th weeks of pregnancy. "These findings provide strong evidence that prenatal steroids can benefit infants born as early as the 23rd week of pregnancy," said study author Rosemary D. Higgins, M.D., of the NIH's Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD). The study was conducted by researchers participating in the NICHD Neonatal Research Network and led by Waldemar A. Carlo, director of the Division of Neonatology at the University of Alabama at Birmingham. The findings appear in the Dec. 7 Journal of the American Medical Association. When given to pregnant woman at risk for preterm delivery, steroid hormones help the fetus's lungs to mature. For infants born preterm, increased lung development improves the chances for survival and may decrease the risk of brain injury. Infants born in the 22nd through the 25th week of pregnancy — far earlier than the 40 weeks of a full term pregnancy — are the smallest, most frail category of newborns. Many die soon after birth, despite the best attempts to save them, including the most sophisticated newborn intensive care available. Some survive, and reach adulthood relatively unaffected. The rest will experience some degree of lifelong disability, including minor hearing loss, cerebral palsy, and intellectual disability.

Keyword: Development of the Brain; Hormones & Behavior
Link ID: 16121 - Posted: 12.08.2011

by Michael Marshall If you believe European folklore, malevolent fairies are lurking outside family homes. Each one hopes to steal a baby and leave her own child in their place: a changeling. If you are a songbird, there is some truth to the story. Cuckoos dump their eggs in the nests of other species, often killing the rightful offspring. Such brood parasites can get pretty savage themselves: greater honeyguide chicks kill their hosts' offspringMovie Camera. Not always, though. The shiny cowbird does kill some of the host's chicks, but not all of them – and sometimes having a cowbird egg lurking in your nest can even be a good idea. As a group, cowbirds get their name because they follow herds of hoofed mammals such as buffalo, feeding on insects kicked up by the animals' hoofs. This may explain why they lay their eggs in other birds' nests: they can't stay in the same place long enough to raise their own young. Shiny cowbirds aren't fussy about who they exploit. Their eggs have been found in the nests of more than 250 species, although they do tend to go for hosts larger than themselves, and individual females can be fairly consistent. Perhaps because they use so many different hosts, cowbird eggs come in a range of colours and patterns. The female lays her eggs around the same time as the host, so that all the eggs in the nest hatch together. She does so when the parents are out foraging – although they sometimes catch her in the act and attack her. © Copyright Reed Business Information Ltd.

Keyword: Sexual Behavior; Evolution
Link ID: 16120 - Posted: 12.08.2011

by Rowan Hooper WHAT was the basis for the earliest friendships? If wild chimps are any guide: support in a fight, borrowing a valued tool, and a bite to eat now and then. Quite similar to our friendships today, in fact. Indeed, some chimps are so modern they have relationships that we would classify as friends with benefits. Primatologists are reassessing the complexity of chimpanzee society in the light of new findings that also suggest answers to a long-standing question: why share things with non-relatives? For the first time wild chimps in Senegal have been observed taking plant foods and tools from other chimps, who don't react to the intrusion. The chimps donating their stuff don't get paid, but neither do they protest. Instead, the trade appears to help build social cohesion. What's more, in another west African study, this time in Ivory Coast, a "market" has been described where chimps exchange commodities in the shape of both social behaviours including grooming and sex, and resources such as meat. Christophe Boesch of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, says we have only recently begun to appreciate the time and energy chimps invest in reciprocal relationships, and he compares chimp relationships to friendship. "These findings have prompted primatologists to use some terms that have in the past been reserved for humans." © Copyright Reed Business Information Ltd.

Keyword: Evolution; Aggression
Link ID: 16119 - Posted: 12.08.2011

By Ed Yong of Nature magazine It is not every day that you are separated from your body and then stabbed in the chest with a kitchen knife. But such experiences are routine in the lab of Henrik Ehrsson, a neuroscientist at the Karolinska Institute in Stockholm, who uses illusions to probe, stretch and displace people's sense of self. Today, using little more than a video camera, goggles and two sticks, he has convinced me that I am floating a few meters behind my own body. As I see a knife plunging towards my virtual chest, I flinch. Two electrodes on my fingers record the sweat that automatically erupts on my skin, and a nearby laptop plots my spiking fear on a graph. Out-of-body experiences are just part of Ehrsson's repertoire. He has convinced people that they have swapped bodies with another person1, gained a third arm2, shrunk to the size of a doll or grown to giant proportions3. The storeroom in his lab is stuffed with mannequins of various sizes, disembodied dolls' heads, fake hands, cameras, knives and hammers. It looks like a serial killer's basement. "The other neuroscientists think we're a little crazy," Ehrsson admits. But Ehrsson's unorthodox apparatus amount to more than cheap trickery. They are part of his quest to understand how people come to experience a sense of self, located within their own bodies. The feeling of body ownership is so ingrained that few people ever think about it -- and those scientists and philosophers who do have assumed that it was unassailable. © 2011 Scientific American,

Keyword: Pain & Touch; Vision
Link ID: 16118 - Posted: 12.08.2011

By Joseph Brownstein and MyHealthNewsDaily In the struggle against widespread obesity that begins in early childhood, new research indicates that schools may be the best place to start a solution. Australian researchers examined 55 interventions in previous studies and concluded that school-based programs were key in getting kids to healthy weights, and there was little evidence that these programs would have a negative effect on young students' self-images. "Obesity prevention programs in general are not harming children," said lead author Elizabeth Waters, chair of child public health at the Melbourne School of Population Health. However, "programs that don't make a commitment to preventing body image issues might hurt children by stigmatizing overweight children or send unhealthy messages about body image," she said. "We looked for information about harms in our review and, while many studies did not report this information, of those that did, there was no evidence of harm with these programs," Waters said. The study is published online today (Dec. 6) in the Cochrane Library, a journal that publishes studies compiled by evaluating previous research in the field. In developing programs for schools, Waters said that adding lessons on healthy eating, physical activity and body image to the curriculum, along with improving school lunches, making students more active during the day and supporting parents to make similar changes at home would improve children's health. © 2011 Scientific American

Keyword: Obesity
Link ID: 16117 - Posted: 12.08.2011

By JOHN BRANCH THROUGH THE NIGHT and into the next day, as the scrolls across the bottom of television screens spread the news of Derek Boogaard’s death last May, the calls of condolences came, one after another. Among them was a call from a stranger, first to Joanne Boogaard in Regina, Saskatchewan, then to Len Boogaard in Ottawa. It was a researcher asking for the brain of their son. An examination of the brain could unlock answers to Boogaard’s life and death. It could save other lives. But there was not much time to make a decision. Boogaard, the N.H.L.’s fiercest fighter, dead of a drug and alcohol overdose at 28, was going to be cremated. There was little discussion. The brain was carved out of his skull by a coroner in Minneapolis. It was placed in a plastic bucket and inside a series of plastic bags, then put in a cooler filled with a slurry of icy water. It was driven to the airport and placed in the cargo hold of a plane to Boston. When it arrived at a laboratory at the Bedford V.A. Medical Center in Bedford, Mass., the brain was vibrantly pink and weighed 1,580 grams, or about 3 ½ pounds. On a stainless-steel table in the basement morgue, Dr. Ann McKee cleaved it in half, front to back, with a large knife. Much of one half was sliced into sheets about the width of sandwich bread. © 2011 The New York Times Company

Keyword: Brain Injury/Concussion; Aggression
Link ID: 16116 - Posted: 12.06.2011

Erin Allday, Chronicle Staff Writer Scientists at Stanford and UCSF are recruiting patients for two clinical trials to test the use of ultrasound waves, as an alternative to traditional radiation therapy, to ease pain in people whose cancer has spread to their bones. Earlier studies of the ultrasound treatment have been promising, and a study recently completed at Stanford and 16 other U.S. research sites found that most patients saw substantial improvement in pain control after radiation therapy had failed to work. The treatment is still considered experimental and is not available outside of clinical trials. It is being studied only as a treatment for the pain associated with metastatic bone cancer, and not for treating the cancer itself. "Radiation is very effective for most patients. But there is still a significant percentage that it doesn't work for," said Dr. Pejman Ghanouni, a Stanford radiologist who is leading ultrasound clinical trials there. "I don't view ultrasound as something that would replace radiation. It's another tool in the toolbox." Doctors have had such success in treating cancer that people are now living years longer after a diagnosis than they did decades ago, Ghanouni said. But as survival rates have increased, so have rates of metastatic disease, which occurs when the cancer has spread beyond the initial site, commonly into the bones. © 2011 Hearst Communications Inc.

Keyword: Pain & Touch
Link ID: 16115 - Posted: 12.06.2011

by Catherine de Lange Chimpanzee brains may be hard-wired to evolve language even though they can't talk. That is the suggestion of a study which found chimps link sounds and levels of brightness, something akin to synaesthesia in people. Such an association could help explain how our early ancestors took the first vital step from ape-like grunts to a proper vocabulary. Synaesthetes make unusual connections between different senses – they might sense certain tastes when they hear music, or "see" numbers as colours. This is less unusual than you might think: "The synaesthetic experience is a continuum," explains Roi Cohen Kadosh of University College London. "Most people have it at an implicit level, and some people have a stronger connection." Now, Vera Ludwig from the Charite University of Medicine in Berlin, Germany, and colleagues have shown for the first time that chimpanzees also make cross-sensory associations, suggesting they evolved early on. The team repeatedly flashed either black or white squares for 200 milliseconds at a time on screens in front of six chimpanzees (Pan troglodytes) and 33 humans. The subjects had to indicate whether the square was black or white by touching a button of the right colour. A high or low-pitched sound was randomly played in the background during each test. Chimps and humans were better at identifying white squares when they heard a high-pitched sound, and more likely to correctly identify dark squares when played a low-pitched sound. But performance was poor when the sounds were swapped: humans were slower to identify a white square paired with a low-pitched noise, or a black square with a high-pitched noise, and the chimps' responses became significantly less accurate. © Copyright Reed Bus

Keyword: Language; Evolution
Link ID: 16114 - Posted: 12.06.2011

“Aging is not a mild form of dementia,” says cellular neurobiologist John Morrison, who specializes in aging. Until recently, many scientists thought brain cells died as we aged, shrinking our brains and shedding bits of information that were gone forever. Newer findings indicate that cells in disease-free brains stay put; it’s the connections between them that break. With this new perspective has come an explosion of research into how we can keep those connections, and our brain function, intact for longer. © 1996-2011 The Washington Post

Keyword: Alzheimers
Link ID: 16113 - Posted: 12.06.2011

Female Ecstasy users show long-lasting signs of toxicity in their brains, an imaging study shows. The neurotransmitter serotonin, a critical signaling molecule, has roles in regulating mood, appetite, sleep, learning and memory. In Monday's issue of the Archives of General Psychiatry, U.S. researchers used PET scans to look at levels of certain serotonin receptors in different regions of the brain in 15 women who had used Ecstasy compared with 10 who never taken it. The study is important, said study author Dr. Ronald Cowan, a psychiatry professor at Vanderbilt University in Nashville, because the drug is now being tested as a treatment for post-traumatic stress disorder and anxiety associated with cancer. "Our studies suggest that if you use Ecstasy recreationally, the more you use, the more brain changes you get,” Cowan said. Investigators will need to know the dose at which Ecstasy becomes toxic before it is used as a treatment, the study’s authors cautioned. In the study, they found Ecstasy use produces chronic serotonin neurotoxicity in humans. Since previous studies suggest that the use of birth control, estrogen level and age affect serotonin receptors, the researchers took those factors were taken into consideration in the analysis. But the authors acknowledged they may not have fully accounted for those variables. © CBC 2011

Keyword: Drug Abuse
Link ID: 16112 - Posted: 12.06.2011